Non-volatile memories, such as NAND flash memories, are frequently used as storage devices for holding digital information in devices that control digital information, such as digital cameras, video cameras, and cellular phones (called “host devices” hereinafter). In recent years, the frequency at which the specifications of non-volatile memories are changed due to the scaling down of semiconductor processes has increased, and therefore memory devices that include a non-volatile memory and a memory controller are being used more widely. Such memory devices include removable cards that can be attached to and removed from the host device, embedded types that are attached to the circuit board of the host device and used, and so on.
Recently, the capacities of internal non-volatile memories are increasing, and non-volatile memories are being more widely applied to moving picture recording applications. When recording a moving picture into a device that includes a non-volatile memory, what is known as real-time recording, where data is written while ensuring a constant write speed, is necessary. Patent Citation 1 discloses a method for carrying out real-time recording into a memory device that uses such a non-volatile memory.
When a host device performs real-time recording into a memory device, in actuality, normal data (data excluding special data such as management information; for example, data of which user files are composed, still image data, moving picture data, and so on correspond to “normal data”) and file management information are recorded in an alternating manner.
FIG. 11 indicates the writing sequence of data and file management information according to a conventional technique.
As indicated in FIG. 11, in the conventional technique, the writing process of normal data DAT and the writing process of file management information FAT are carried out in an alternating manner. The file management information FAT is, for example, file management information according to the FAT file system; the writing process of the file management information FAT is composed of a writing process for duplicated file allocation tables FAT1 and FAT2 and the writing process of a directory entry DIR. With a memory device according to the conventional technique, the writing process of the normal data DAT and the writing process of the file management information FAT (FAT1, FAT2, DIR) are performed so that data/information is identified based on its address, size, and sequence and recorded into different regions within the non-volatile memory, so that the writing of the file management information does not affect the performance of the writing of the normal data.    Patent Citation 1: Patent JP2006-178923A